Effect of Silica Fume and Polypropylene Fibers on the Mechanical Properties of Pervious Concrete

In this paper, Silica Fume (S.F.) be used for reinforce pozzolanic cement paste and the effect of using many weight percentages as (0%, 5%, 10%, 15%, and 20%) to lessening the concrete weight as a cement replacement in concrete mixtures on the mechanical properties was studied. High range water reducing added to decrease the water demand of the concrete, when silica fume added. Moreover, (0.025%, 0.05%, 0.1%, and 0.15%) are the proportions of polypropylene Fibers (P.P.F.) by volume, which used to improve the pervious concrete mechanical properties, physical, and mechanical properties of hardened concrete containing voids ratio, compression strength, and flexural strength and, splitting tensile strength investigated. The density of reference pervious concrete that was get through the experimental work was( 1835 Kg/m3 ) at (28) days ,it permeability coefficient (K) and voids content was( 0.324) cm/s, and (30.21%) successively, The results shown important increase in compression, splitting tensile and flexural strengths of pervious concrete containing silica fume and (P.P.F.) comparison with reference pervious concrete. The mixture of (10%) of (SF) and (0.1%) of (P.P.F.) gave optimum increased in the compressive, flexural, and splitting tensile strengths compared with the reference mix and the results (47.8%, 29.21%, and 24.41%) respectively.